An enzyme immune assay for serum anti-acetaldehyde adduct antibody using low-density lipoprotein adduct and its significance in alcoholic liver injury.

An acetaldehyde (AcH) adduct was prepared using rabbit low-density lipoprotein as carrier proteins. An antibody against this adduct was raised in Watanabe heritable hyperlipidemic rabbits and cross-reacted with human low-density lipoprotein and bovine serum albumin adducts. Using this antibody, serum anti-AcH-adduct antibody levels were measured by a direct ELISA method in 56 Japanese adults (healthy adults and patients with nonalcoholic gastrointestinal diseases, alcoholic liver injury, or alcoholic pancreatitis). The antibody level (mean ± SD) was 22 ± 10 μg/ml in healthy adults, 22 ± 11 μg/ml in nonalcoholic gastrointestinal diseases, and 16 < 13 μg/ml in alcoholic pancreatitis. These antibody levels tended to increase with the progression of alcoholic liver injury, starting from fatty liver via hepatitis to cirrhosis, 29 ± 24 μg/ml in fatty liver, 35 ± 29 μg/ml in alcoholic hepatitis, and 46 ± 54 μg/ml in alcoholic cirrhosis. The antibody level in patients taking 100 g or more of ethanol per day tended to be higher, compared with those in people taking less ethanol. A follow-up observation revealed that alcohol abstinence after hospitalization raised serum anti-AcH-adduct antibody level in some patients and kept it constantly low in other patients. The immunohistochemical study using the anti-AcH-adduct antibody revealed the presence of adduct-like substance in hepatocytes of Uver biopsy specimens obtained from patients with alcoholic liver disease. The results indicate that the anti-AcH-adduct antibody may be associated with the progress of alcoholic liver diseases.